There is provided a process for preferential conversion of a racemic alpha -aryl propionic acid into an optically pure S-(+) or R-(-)- alpha -aryl propionic acid. An illustrative process is disclosed to prepare S-(+)-ibuprofen involving esterification of racemic ibuprofen with an optically active alkanol, fractional distillation of the resulting diastereomeric esters, racemization of the undesired diastereomer, and optional hydrolysis of the S,S-diastereomer.There is provided a process for prefe...

In the carbonylation of isobutylphenyl ethanol to ibuprofen in the presence of a phosphine ligand-stabilized palladium catalyst, it has been found that the catalyst complex will precipitate from the organic phase of the carbonylation reaction which includes the ibuprofen product. Precipitation of the catalyst is facilitated by removing the aqueous phase from the reaction and removing any solvents from the organic phase. The precipitated complex catalyst can be recycled without further treatment....

A method is provided for the preparation of alpha-aryl-propionic acids such as ibuprofen by carbonylating the corresponding 1-arylethyl halide in an acidic aqueous medium containing a palladium catalyst. In the preparation of ibuprofen, 1-(4'-isobutylphenyl)ethyl halide is reacted with carbon monoxide in an acidic aqueous medium containing a palladium catalyst.

A process is provided whereby S(+)-ibuprofen or R(-)-ibuprofen L-lysinate salt is produced by selective precipitation from a mixture containing enantiomers of ibuprofen and L-lysine. The quantity of L-lysine is not more than about a molar equivalent of the quantity of one of the enantiomers in the ibuprofen enantiomeric mixture. Upon precipitation of one ibuprofen enantiomer from the mixture, the overall precipitate and reaction mixture can be held for a sufficient period of time at a second tem...

A process is provided whereby S(+)-ibuprofen or R(-)-ibuprofen L-lysinate salt is produced by selective precipitation from a mixture containing enantiomers of ibuprofen and L-lysine. The quantity of L-lysine is not more than about a molar equivalent of the quantity of one of the enantiomers in the ibuprofen enantiomeric mixture. Upon precipitation of one ibuprofen enantiomer from the mixture, the overall precipitate and reaction mixture can be held for a sufficient period of time at a second tem...

There is disclosed and claimed a process whereby S(+)-ibuprofen L-lysinate salt is produced by selective precipitation from a mixture containing enantiomers of ibuprofen and L-lysine. The quantity of L-lysine is not more than about a molar equivalent of the quantity of S(+)-ibuprofen in the ibuprofen enantiomeric mixture. The mother liquors after separating the above salt are enriched in R-ibuprofen which is racemized by a novel thermal racemization process and may then be recycled.

A process is provided whereby S(+)-ibuprofen or R(-)-ibuprofen L-lysinate salt is produced by selective precipitation from a mixture containing enantiomers of ibuprofen and L-lysine. The quantity of L-lysine is not more than about a molar equivalent of the quantity of one of the enantiomers in the ibuprofen enantiomeric mixture. Upon precipitation of one ibuprofen enantiomer from the mixture, the overall precipitate and reaction mixture can be held for a sufficient period of time at a second tem...